224 



FRESH-WATER ALG.E FROM BURMA 



Long, sine proc. 36/*, cum proc. 44/*; lat. sine proc. 26/*, cum proc. 38/.; 

 lat. isthm. 11*5^. 



ifa&.~MansaDg, near Hsipaw (No. 24193). 



163. Staurastrum leptacanthum Nordst. Desm. Brasil. 1869, p. 229, t. 4, f. 46. 



Long, sine proc. 34/*, cum proc. 86/*; lat. sine proc. 22/*, cum proc. 82 M ; 



lat. isthm. 11*5^. 



Bab.— In the Kan-gyi at Mudon (No. 24505); abundant. 



164. Staubastrdm sexangulare (Buln.) Rabenh. Krypt. Fl. Sachs. 1863, p. 621; 



Lund. Desm. Suec. 1871, p. 71, t. 4, f. 9. 



Didy mocladon sexangulam Buln. in Hedwigia, 1861, p. 51, t. 9A, f. 1. 



Var. bidentatum Gutw. Alg. Ins. Java, 1902, p. 606, t. 40, f. *63. 



Forma cum denticulis prope basin procesauum non bidentatis ; etiam cum verrucis 

 emarginutis ad apiceni inter processus distinctis. Characteribus ceteris ut a cJ. 



Gutwinski descriptis. 



Long, sine proc. 44/*, cum proc. 86-92/i ; lat. sine proc. circiter 42/*, cum proc. 

 104-107,*; lat. isthm. 16/* (PI. xvi, fig. 16). 



Hah. — Mausang, near Hsipaw (No. 24193). 



The specimens examined from Burma possessed all the main features of Gutwinski's variety, 

 such as the large size of the cells, the longer processes, and the more upwardly diverging superior 

 •whorl of processes, but they curiously did not possess the character from which he named his variety. 

 The denticulations near the bases of the process were in no instances bidentate. Another rather 

 curious fact is the presence in the Burmese specimens of the emarginate warts on the apices of the 

 gemicells and between the bases of the processes. These emarginate or bigranulate warts are a 

 feature of typical St. texangulare and also of all the varieties we have examined, whereas Grutwinski 

 expressly states that they were absent from the specimens he examined from Java. 



Genus: Onychonema Wallicb. 



165. Onychonema ljeve Nordst. Desm. Brasil, 1869, p. 206, t. 3, f. 34. 



Long. 16-17/*; lat. sine spin. 21-25/*., cum spin. 31-36*5/*: lat. isthm. 6/*. (PI. 

 xii, fig. 8). 



Bab. — Mansang, near Hsipaw (No. 24193). 



Numerous spores were observed of a large form of this species (long. 21-23/x ; lat. sine spin. 

 28-30, oum spin. 41-44yu,; diam. spor. cum spin. 23-26/x), but we are uncertain whether they should 

 be regarded as zygospores or aplanospores. They were very similar to zygospores of this species 

 which we have examined from the United States {vide "W. & G. S. West, Some N. Amer. Desm. 

 1896, p, 232, t, 12, f, 16, 17), but possessed fewer spines. Never more than two 6emicells were 

 observed attached to one of these spores, and always at opposite sides of the spore. In size the 

 spores were relatively small, and they have the appearance of having been formed from the contents 

 of one cell only {vide PL xii, figs. 9, 10). 



166. Onychonema compactom sp. n. (PI. xii, figs. 6, 7). 



O. magnum, fills compactis non tortis ; cellulae 1^-plo latiores quam longae, 

 profundissime constrictae, sinu perangusto-lineari ad extremum leviter ampliato 



